Spade's tone carried his own complicated emotions, an emotion that he had been bottling inside for quite some time.
As he said, Spade messed up, and he messed up real bad.
There was always this kind of responsibility that had already burdened his shoulders ever since he was born. Spade was born to be the emperor of a collosal empire.
Between his responsibility and his own desire, there was always an ambiguous thin line that Spade was afraid to truly cross, no matter what. He had a lot of things on his mind, and his duty was even more so.
He was a reasonable crown prince and ascended the throne in the same manner. Actually, when he took the throne, Spade always had this impression that he didn't sit in such a high position for the sake of it; he was given a huge responsibility that he 'must' take.
